Process for producing an oil sorbent copolymer and the product thereof

Abstract

The present invention is directed to a porous copolymer micro-particle having a high oil absorbency. The method of the present invention comprises the steps of: dissolving at least two polyunsaturated monomers in a water-immiscible organic solvent to provide a monomer mixture containing at least about 60%, preferably about 100% by weight polyunsaturated monomers; adding the monomer mixture to an aqueous solution, preferably having an effective amount of a suspension stabilizer dissolved therein, to form an organic/aqueous biphasic liquid system; vigorously agitating the biphasic liquid system at a rate sufficient to cause the water immiscible organic phase to be suspended as micro-droplets in the aqueous phase; continuing vigorous agitating during polymerization of the monomers in the suspended micro-droplets to produce a microporous polymer micro-particle; and separating the microporous polymer micro-particle from the organic solvent to produce a microporous and oil sorbent polymer micro-particle having a mean unit diameter of less than about 25 microns.

What is claimed is: 
     
       1. A solid microporous oil and water adsorbent micro-particle comprising a copolymer of allyl methacrylate and an ethylene glycol dimethacrylate, in a mole ratio of about 0.5 to 2, said particle characterized by having a mean unit diameter of less than about 50 microns and a total sorption capacity for mineral oil that is 72% by weight or greater. 
     
     
       2. The micro-particle of claim 1, wherein the molar ratio of allyl methacrylate to ethylene glycol dimethacrylate is about 1:1.22. 
     
     
       3. The micro-particle of claim 1, wherein said ethylene glycol dimethacrylate is a member selected from the group consisting of monoethylene glycol dimethacrylate, diethylene glycol dimethacrylate and triethylene glycol dimethacrylate. 
     
     
       4. The micro-particle of claim 1, wherein said ethylene glycol dimethacrylate is monoethylene glycol dimethacrylate. 
     
     
       5. The micro-particle of claim 1, wherein said total adsorption capacity for mineral oil is 85% by weight or greater. 
     
     
       6. The micro-particle of claim 5, wherein said total adsorption capacity for mineral oil is 90% by weight or greater. 
     
     
       7. The micro-particle of claim 1, wherein said mean unit diameter is at least 1 micron. 
     
     
       8. The micro-particle of claim 1, wherein the mole ratio of allyl methacrylate:monoethylene glycol dimethacrylate is about 1:1-2. 
     
     
       9. The micro-particle of claim 7, wherein the mean unit particle diameter is from about 1 to about 20 microns. 
     
     
       10. The micro-particle of claim 9, wherein the mean unit particle diameter is from about 1 to about 16 microns. 
     
     
       11. The micro-particle of claim 1, further characterized by having a particle size distribution that spans no more than about 100 microns.